Improvement in the manufacture of nitro-glvcerine



fully.

fidiiiid %tau5 EDWARD A. L. ROBERTS, O1 "ITL'SVILLE, PEN. SYLVAXIA.

Letters Patent No. 112,848, dated March 21. 1871,

IMPROVEMENT IN THE MANUFACTURE OF NlTRO-GLVCERINE.

The Schedule referred to in these Letters Patent and making part of the same.

To (111 whom it may concern Be it known that 1, EDWARD A L. om-ems, oi Titusrillc, in the county of Urawibrd and State oi' Pennsylvania, have invented a new and useful lmmovement in the Manutaciure oi' Nitro-Glyccrhw; and I do hereby declare thatv the following is a full, clear, and exact description thereof.

Nitro-glycerine is manufactured by mixing nitric i acid and glyccrine, which, on combining, form that ari ticlc. The process is most convenientlycarried on by pouring the glyceune into a bath of mixed acids composed of nitric acid one part, and sulphuric acid from two to two and six one-hundredth parts. To this acid I bath is added gradually the glyceriuc in the propor-' tion of about one part glyccrine to nine parts of the I inixtd acids.

in this process water is generated, as is supposed, i partly by the combination of oxygen and hydrogen i set free in the process, and partly by the liberation oi l the water held by t] glyceiiuc.

My invention consists in reducing the prlmortionate amount of sulphuric acid used in the first instance in the acid bath, and gradually adding the amount thus withheld oi'sulphuric acid during the process of manutartnre.

The result obtained by this change of process is to increase the yield of nitro-glyceriue from a given amount of glyecrinc and acids.

To enable others skilled in the art to use my improvement, i will proceed to describe the process more The apparatus employed may be oi any desired construction, consisting substantially ota leadon or lcad-ljncd vessel or mixing-tank, with suitable devices for mixing the tglyccrinc and acids by agitation or by creating arapid circulation of the contents of the tank.

'lhcroshonld also be suitable means for cooling the contents of the mixing-tank, so as to prevent decomposition by reason of the generation of heat in the lll'UCHSS.

hi this mixing-tank is poured the mixture of nitric and sulphuric acids in the proportion or" two parts of hit! mid to from two and a hall parts to three and a hat 1 'ts of sulphuric acid, or thercabout. The glyccrinc is then slowly poured into the acid bath'iu a continuous stream, and, at the same time, there is poured into the mixing-vessel, in a separate stream, at least so much of sulphuric acid as the acid bath lacked of being in the ordinary proportion before stated.

.lluriug, the process the contents of the mixingvessel are kept in rapid motion, and the resuit is that the amount of nitro-glyct-rine produced will be greater in proportion to the .amount of glycerine and acids used than when the whole amount of sulphuric acid is mixed with the nitric acid at the beginning of the 1111 t 1hi -sult I suppose to be owing, at least in part, to the tact that, as the process is carried on, the amount of water generated iucre.. and the nitric acid becomes more dilute, so that the gradual addition of fresh acid takes up the water thus generated and keeps the nitric acid sufficiently strong to act on the glycerinu.

Having thus described myimproved process,

What I claim as myinvcntion, and desire to secure by Lcttcrs Patent, is-

lhe process hercinbcfore described of making nitrogiyccrine by graduallyincreasing the amount of sulphuric acid in the acid bath simultaneously with the pouring in otthe glycerine, substantially as described.

' E. A. L. ROBERTS.

Witnesses I Tan. 1. SHAFFNER, '1. 0. BREGHT. 

